SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '14b7f4c6307bed42ce261d23a616b3d5f5b0a41e11dadffa730b576b4ab08aaa' 
  AND token = '2niWTNpo47Fcvlfb5pQJ3rlZQhJxlPBK7PUlKsoMCdA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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