SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'aac483d49d209e034d1f574b0caac64f15af92be8e526189e271fd764bb6d186' 
  AND token = 'LyEi3tAk0/DieFrSjbBMxTWm/UnP0rPcqBB1bS0u3tI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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