SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98738e6c20fc67bc552e7de6faff9cb62e2c526aa6a7a594eb9f4945f8eeec4c' 
  AND token = 'yR+CjeIJ591Qngnv/+h5J5DXy+QgRpIxP5gA9T3A9GA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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