SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa569cfc92284df8d24250cafb8c78bfd999851ab725e2f3d970c092e23d0529' 
  AND token = 'wzjmjYXPFzwcKsFlGZcEI1y4WeVWvQBmaLKj1sChDvI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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