SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f62cf79140ca8d614707c93894ed1ccdd02a73d63e3ed621eefa7e7d0899ed33' 
  AND token = 'FBqNreCKJvBOUlorlAWtZmJ9s5NMTkp1AFvEv0t1dew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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