SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '009e0bb098891a133ee6838a8da107cdecfdc6d004fa045e21b028bad706931a' 
  AND token = 'g2xSQDiG5MXKNVinZUEwb8UvGcMouGYzDGAo4Av0azU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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