SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8924bb45ab93918528f5030267cf821eef1fbd5a9d71e012759a087a8f12941d' 
  AND token = '96gvUqw1/w+YqbkcsdBWjWtLn+qmywROAS9xNphtQ1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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