SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '925d067b9b5b6a58ef3118fe52008002de967c1338a031d2025ae28990a3e298' 
  AND token = 'PbHStpTM/OXdW5gUellsm23BN9vQNjbZwxRLhzo5w1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}