SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a1183cc6b0e0607e349cba790d041c800b06171d973f5e637dda17ac53c2632' 
  AND token = 'PNpTE6tgt1nd2j3PoMFXVB2RfgexfNL0PSmYTGHtsYw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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