SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '456c63ad606f6a58631e12f59596f8605c6e48de3852285bae11f47901e2ec9a' 
  AND token = 'vdiCuayGg1/bWuUVNzKneCMft9cu6HOUbiJsYPfkBlo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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