SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cef7d1ec678dd5fe66322ac549753358cd711a1506bcefc62119cec8a16cafa7' 
  AND token = '2goByr2Cak7I6JzC653TGqzR/QZzFpVSEn4uwtEiR3E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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