SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7ebf5965654f2bf4d305e2fd7f51349b67cd136783c4c161579b481c14badd8c' 
  AND token = '+qDVsba/bAO4wF/+Ajo9uQ6JHC/L4d2fOGvCx1rwURQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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