SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f19dd61778365ed6a7921f1e350e9a67a539cbeee84c1e8e2bcdcfa052bff35a' 
  AND token = 'E2Br+GgDv55eNie1pjYE46W3v3jQpSG23xcbxhh5qZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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