SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e618805641f0f364cf81452713ea0dc2026313ae989867477e1449e2da3e96e6' 
  AND token = '+PZWYweBdRvhBDmQgh7/ZDoMobzoiQJtygPOjtXj0AM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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