SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e349ec573e841a940cd360b9ea2e4fb700ee1e7bbb0ed1d61d300275d65725d6' 
  AND token = 'NlfBS4RjRWK+HeCzVyo5WgsAi8ABnwcMhiP1Kj51IyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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