SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b93d4d20dc6bceefb03f27c9fc73f3b6bb9620f3b6716fa1758ae14f5930e146' 
  AND token = 'vKUQaLZpFtaF/KX4eyGryYzxXzIgHNe38V3QoV3BJlI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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