SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cab1b17bb4aa1926be6eca09bed361bc140261c64eb304438f1326ac4a9131c5' 
  AND token = 'rjzUQP2AySkwKE016wCDAuyXz90stpcCjmIEf4p2THw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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