SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4281879c757048d5d7b4c927c58caa87590dacdcded76d3da2ccd1ed9156a692' 
  AND token = 'FVoVa+5+7pzjPJ0Dqj6OqgSZ04QItdfRDvreFzyC/dg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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