SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cefa66fe57514a082cddcee22528ef85ecd53544025e7ab5b8ff63d9d3e9dfd4' 
  AND token = 'VfWS2p43AWS26ehgLuSGoZtJJ3wYNmd3EEXcAL5mq4w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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