SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85512308ea0ed2167c1d9e18db9343fdb2e9aa1a493c8ef57ab926a98fb4e8a8' 
  AND token = 'ygK+QHPFuxIRpkzkZ3gPJVUgwSszsxw0gj1d4Zq+emY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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