SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee48d954e7663f85df775c7fdb5fa0b487ed5662aa4393dbd22b46e19cd1252c' 
  AND token = 'Us+kXW0JSFhg+rfLjQP7L51ITXidYKTzpcCyIIVKGCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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