SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f49a3208028a328bdb3e8a8b7846b13fdfca98eba2cd14755bb8bd5ebc1085a' 
  AND token = 'w62+yGgiGEN5JdcYelX8COW+fTufXTkvzC0UfEGfV38=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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