SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e4d2b7ddf8df966c5e16edafa124fb12a6b7ffadbc1a092c3aba49433db4a334' 
  AND token = 'TSugM5bMjSFrdzl3OXpTLlyavwT7pZWQ5Fp+IlKpnFQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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