SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4b26e129a56d12324dca8af7a3b583c1186f7d1a49e77b92ea9d5d7f311b8cf' 
  AND token = 'Ge/h8hZr+5Fuqeiawu7Ck9rE/fGxMJmDubOKLHagmiU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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