SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b32625e7692f60a6e9d105efd70b62ac60f3f75ecc6658daef452f5456a7a928' 
  AND token = 'OBN0zfX5baR4qBUFdegjGj260L3m6gYuwAaw4cPHvig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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