SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be76b5b24ef8cd1bfd3dab1ac2f8a7d32882469d1bfbe2f3db613715aa5dadae' 
  AND token = 'GOeJMo8e2sAzcUlSCzw/MsE2R37p9H0H/8tF689rwWE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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