SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6bf9c3e031450e49ad38c9b39086bde7ac66d052b3fdf276716e17dcd9ab8b15' 
  AND token = 'yr6FF0S+QxZEVMW7NxL7Alye96qDDCTsboyuUKjRTeY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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