SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eada2fb38fdf012781c2b77ed940dc362d37347b132cc4a1928b741b70f4f137' 
  AND token = '7AypL/zs+ljhryY5jmSQwkkNqBPKOfgeLlfeP5wHgYU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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