SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'feebae457ba46cc4c8c8c446404e30f946d25365903467f0b00ca3556e86dc31' 
  AND token = 'cVZfTutnYRqQXrVBzVnLIdKbWXuvHLsVmoF+UkKLVHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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