SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb5e55e5c80ed749b5864692975a74bc69c66173d479888a2a0ef0f4bf0663c3' 
  AND token = 'FqvFxKmmJefB/lasqfOHjcG2Ptem2XGwr5ZLs85GLKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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