SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '36980d9ba6dc0c2118b251434fa4f62d4e67ba425705915d2ad668e353031939' 
  AND token = 'REO6jCr9Si7BMyMME1qJKyDgf1pFRK5weQ+6LOghUYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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