SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18c550be7db109331e399006304a1193a281320dfdfaf7dfb8c271f77f7a3d53' 
  AND token = 'aOJ+d1U4AlhFBVIukdUNQiRfj8cDJQjfaObzVb+3Jeo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}