SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c018d54a929ece668a73ba4719fa0ec47c6265a93c654e054afea04ff2e3e7fd' 
  AND token = '0W4KQyJcqb8ews4amBgzrL2yNy3JC3YKZhFy9FtlgqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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