SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a3438facdea3df2c9fde3e6b2958001f287be51f7cf7d9b2dcf43e930a8f83c1' 
  AND token = 'zhon6U6m7Rr3upmeLN2HIc3uPqzQ5nlYvftGGOpV7gA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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