SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '584a84ed63a39fe555a6e4055d88f4302135f9d0b1b87740164bfc1f4e79414b' 
  AND token = '43zzcJbriMHDbXvCRmUoFOjNk2EfERafbo07gfLMGGE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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