SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e382a42acb7bc7067ebb9f937706059b5e5191ed6df8f0656233787d86497f9' 
  AND token = 'HirGxHhFBcIvJEQ0vNWPq+BPQ4grG7qGc426rXsmRE8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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