SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7a85084c293bed3f9058692d26000d7dd514a056cb95d479e85b0b3b333dd1c1' 
  AND token = 'Ed6SbrmU6MdaKaSjGRvJ7H41QnM8WphyqcYtHCtBkR8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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