SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d6c9b6c290c3ef9f965f6590425f820ef8cd74fd94ba52fffcb4642ce9174d6' 
  AND token = 'EDqM13I9IMLGWZ74sWIkK+hdrIQB1x2WY34SaKYqX6s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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