SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e17925951d84d4b438e7ddb4144afa05f05251dd3c4060ea55e5b0441c30eae3' 
  AND token = 'J/sMZyw58SZErPyY9esasYDkU15k0+iCkRBIZAdObc4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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