SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c0511716d363d3fd8c3b9f233bf7220ef04261e452180ed84a7382e2aef0a10' 
  AND token = 'YZ2hl5qm07TUss1E6cID8lDPPzUzFAH65yiZjN3LJ0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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