SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b7b6187bed3394db59627bf4979707173f2f865a14ba82af90b157dac4705a9' 
  AND token = 'GZg3MTytk1TimIk65lWWpXAYzLfkO3DGtQO41KlqhV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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