SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38aa741c3b7953d2a2a997c35869acef07c25f32f502b83ed5f4cbf5907b3100' 
  AND token = 'cILKeJA2pQRQgmUMCD/EOrp9+5i3N8L8g5Pz9Fh50sk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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