SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c92ba49a1b792f1bf429408aae4930d930cb2f23356e898b4e32ff4ba0895c3e' 
  AND token = 'VJjz1NYXXB48LLzIF59jNPIA+f9vOg+EaTj1TUlhgd8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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