SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58be2c75ab9c06f66073dae945f062d83f266f131c943d66292e0525d6cb7e9a' 
  AND token = 'TJHfvF4nRIZqlPGYqU4kIf2Ou8NB9xzRZ5TW0Pweb+s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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