SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f6643b2ded3616964fd2de63eaa79b589a52b32e01bf7453532ef3ad6b4b4311' 
  AND token = 'tfd8RSk25CSMv0WPpWT2YDeupqashTwo+9ujNg+Xs00=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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