SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89c2cc5938ee0c11d65c34f47871d5a428afa2c820ab23b84840f889ac5783c6' 
  AND token = 'o835pRwH4dPrVkKMDIm1+1Q9OX0dSAqT/Nd0GaozU/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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