SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7301ffb590e68ca05a59ddd29dabb2bd090e22a02923edd133efb6b570c875a' 
  AND token = 'lC6Ag3VpCVTz2eZuUPoSH1UKnhbbs5jAXpLH46xgiyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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