SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08646935749cdde60d60d714669a6e0580cb1c46d92d4ef6fed0392891c072fc' 
  AND token = 'jpjfxxZHEOcXdgHbandWG7PlWQxWXTWws0/LbHuvGCs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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