SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2def382ff81fff1b6a9278ee0f662206955af3bddb95d7779217b78de025e76d' 
  AND token = '/vdJxYBX+vVLqCN7ZwMWJqZvjZFYykTqrBcSCJDRqoA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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