SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f34688fc7e4c7ccbdbf46b63b002ee94933d5a0458e8a1b53376e45596dcc61' 
  AND token = 'ZNk11hFdAY3t2Enxa2cenIRwGECrEjbDbVkRhhsPVJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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