SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b22f2baf9821b573de04cf3ad33c13dccc329d2b74c3632c66befccb155e4120' 
  AND token = '2cFviesezDawm7Y2k5y8RYAq/aSJJxhZ0CiP8Cas+Ss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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