SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7eb6952e187e4940db9dcd46fcf391087d4421aba4f2bbcb319c2e6f5ef5f409' 
  AND token = 'yaQmrZQ5aWh/KBhoQFRUnxbqlLr+FbNDfzV33QKcneg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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