SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0759861791f73d7b12e7a517f17d591a948af2a2c8fc58e0b398c72a46435cb1' 
  AND token = 'ft/mSAXogxj4+vu8FB33KV5IdzMDgvQT7FmVpxtHmig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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