SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4c382fc24152d47aaa7ef0f59609359d2a7573227adda0773853ed9d1f32e85' 
  AND token = '/08kK3MRyjm2iBhwlMNu4B5GTcEetjM9q4TFgUmSY7c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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