SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a6acfe5278b082e85cd80b387f5fadaa980209e7254552196874c4242131ba66' 
  AND token = 'iFJ9o/RiFuEcCvfCDdv+X5GGsf/1ceqcBl4XFzGvRmA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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