SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba15df022888b7db469d40b6f52bbe8b1ad5a33b25366f246fe9783bbf2f5dda' 
  AND token = 't7gIWlv5vkH47D97dUAmF8JPqiGCDtpBBux+pFrKBDs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}