SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd8fc6512fb41bd2551766277ea0ff2c6f53864631d68bd11de7792f6767f5b60' 
  AND token = '1Cgero8AvtDGBLpJaS46NsJpHy6pbylNiWr1MHeBCDg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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