SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8e90959e3a3cdb47103ac90c485f9714a8cf19ee6d6833c9b98b63cddd0cb8f9' 
  AND token = 'WYQC/6viSN8d+Onhk2wrMIByOF2AspXx9tQggwjpGxQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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