SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05f609d5a3d1f923e87f38349fe4dd24e9a48aca4b99284681f0b96db91b2756' 
  AND token = 'DGBW/NtQcNGPbtFhBQQfxUrojUMTEzHF2rhZsF5WWFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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