SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '693a5bbbc1ba60352545b94cb7bec2927448f37df513a2ab384397317a0b8760' 
  AND token = 'PjfqsRrwwPYv3xMOdEMqB9LW6erKfpNq77mIIhQFO+k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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