Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6d887fa6fd5d90a26663b443268ada4b14763e5ef999adfbdeee9ee6a9063a1' 
  AND token = 'fZleRnzLAJOmIi+A+i8xhOo/NXp+q1hJN+g1bKqCF6c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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