SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f743533149b1f6ad2f7f2faebce9d70b9544f4327f2ef6b61878f818ce66779b' 
  AND token = 'X74xvtl5mX4tVwZQF5irESDAeDSf/a7M1bpCCPTLTsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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