SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa60de71b852782820abdbbf8e12a908f4c4a50c28f66c3193d173ac92700f3c' 
  AND token = 'AVpRgmjZCD9cfSpFV90z/ICSi+dnqqkK/zTN1cJU6QE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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