SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8f374e7f1531767ef836e7fecd9f60341c585e46b0fdc003b20e6ae937d68214' 
  AND token = 'ftjwUM4YzILRQd4xHRF2znUM9EY+syFwhKFwQf6C+q0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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