SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9274a521ddbc408f16a3025b2109c7100884f00d9565474793efb39ba1017215' 
  AND token = 'kPFWyPPDkjcXVrFdGpPYla6ppASp/qDRfpcy3TjFSFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}