SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '89a6411010fb17fbc4cfe78cd9fc9c03b9b757289ef04c154eea7cd27d27f660' 
  AND token = 'BodOFRAQ2/28gLB7b3FnkVzyskLBGtKR2nHSNhZXM5s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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