SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc7c88aff70dd698d6c7aec52cc5681ec95239fb1bdbe55f672276218d9f070a' 
  AND token = 'J2K0lNoalPAJWBVOBhe9wQweEbAMnlWPIIkE+/KETLc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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