SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '86ad0be617632735fa019e95675fc3a5ce57fee1ed1333cf57d11f2b1db4d03c' 
  AND token = '2DT2C65a5sF4XqY/Z9VksDXP6w3kNxByxIQC8B34hWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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